The basic purpose of a transformer is to convert electricity at one voltage to electricity at another voltage, either of higher or lower value. In order to achieve this voltage conversion, conductors are wrapped on a core which provides a path for the magnetic flux. The conductors of the transformer may be wrapped using a plurality of techniques such a helical winding, layer winding, disc winding, foil winding, foil-disk winding, etc.
A transformer winding can include only one big and thick conductor wrapped on a core of the transformer. A problem of this solution may be that the width of the conductor in the radial direction may lead to undesired axial eddy losses in the transformer.
These eddy currents are induced by the magnetic flux generated by the current flowing through the winding, and they depend mainly on the module and direction of the magnetic flux.
In order to reduce the axial eddy losses, a conductor of the power transformer winding can include several parallel flat conductors along the radial axis of the winding instead of one big and thick conductor. These conductors may be parallel and radially adjacent with respect to each other along the total length of the winding.
A problem of this solution may be that recirculating currents may appear, which may cause extra losses and consequently an overheating which could degrade prematurely the insulations and consequently lead to an electrical failure.
The present invention aims to provide a transformer which solves at least partly the above drawbacks, by improving the performance of transformers with several parallel and radially adjacent conductors.